Conference grant support is requested for the ninth and tenth conferences, which occur biennially and have been devoted to the use of radioimmunoconjugates in cancer imaging and therapy. Due to the regulatory approval of both naked antibodies (CD20 and HER2/neu) as well as drug-conjugated antibodies (Myelotarg), as well as a large number of other antibodies being in late-stage clinical development, the program is being broadened to include all potential antibody constructs, with emphasis on clinical studies. During the 3-day program, topics of molecular structure of therapeutic antibodies, applications and mechanisms of naked antibodies, drug and toxin conjugates, radioimmunoconjugates, cytokine fusion proteins, pretargeting methods, and anti-idiotype antibody vaccines will be covered, including brief overviews by leading investigators in these fields. However, the emphasis will be to attract proffered papers by new investigators in these areas, and permit a large number of oral and poster presentations over the 3-day period. As in the past, it is anticipated that the proceedings of the conferences will be published as supplements to major cancer journals, emphasizing the inclusion of new, original results. These proceedings therefore enjoy widespread availability and attention, thus attracting new investigators to participate in the conferences and in their published proceedings. The planning committee (partial list) represents leaders in these fields from academia, industry, and government. The conference chairman, Dr. Goldenberg, has secured two outstanding scientists as co-chairmen, Drs. Ralph Reisfeld (Scripps) and Edward Sausville (NCI).